Gunmen killed eight people Sunday night at a religious gathering in the southern Pakistani port city of Karachi.

An additional eight people were wounded, an official at a local hospital told the Associated Press. Gunmen first threw grenades at a building where a Muslim Sufi cleric was receiving his followers before opening fire.

Antagonism between the Sufi-influenced majority of Pakistanis and a minority of Sunnis has led to increasing violence and thousands of deaths from terrorist attacks in recent years, particularly in the north where the Taliban has a strong presence.